Assessment of outdoor thermal comfort in a suburban university campus with the use of ENVI_met program

Open spaces where people spend their leisure time and engage in various activities have always been considered as a part of a successful environment. However, the conditions of open spaces have been extremely important for people to use and further enjoy these open spaces. In a suburban university campus, where the high population spending all day within the campus has been considered, the importance of open spaces rises. Yet, understanding the issues affecting open spaces has been crucial; in accordance with that the characteristics of urban microclimate and outdoor thermal environment offer new opportunities for the improvement of open spaces. Modeling of an urban microclimate has been fundamental at this point, as it allows understanding the present and future microclimate dynamics of open spaces. Although there have been numerous tools and indices developed for assessment of outdoor thermal comfort, due to the complex frame of parameters included, their use has been disregarded during the preliminary/post design process. For this reason, the aim of the thesis is to propose a model in order to inquiry the impacts of the parameters on outdoor thermal comfort and create an assessment methodology for open spaces. Further, the proposed model has been applied on a suburban university campus with the use of a simulation program, ENVI_met. Outputs obtained have been used for evaluation of meteorological and physical environmental parameters over open spaces. In addition, outdoor thermal comfort perception has been simulated with the use of BIO_met tool embedded in ENVI_met program, according to PMV index. The effect of user-related parameters, such as clothing, activity and height-to-weight ratio has been examined. As an essential "tool" in urban design, the impact of vegetation, specifically tree, on thermal comfort perception has been investigated, as well. With simulation results, the effect of environmental and user related parameters on outdoor thermal comfort has been determined. Air temperature and exposure to solar radiation have been affecting the outdoor thermal comfort to a significant extent. Wind direction and speed also affect the outdoor thermal comfort. As highlighted through literature review, not only the meteorological parameters, but the physical environment affects the outdoor thermal comfort remarkably. The geometry of the buildings, surface materials and tree presence has verified their impact on outdoor thermal comfort. The geometry of buildings has been affecting the wind pattern and solar radiation access; as a consequence, the PMV values have been changed according to the building geometries. Additionally, the presence of trees has the crucial role in the summer season and again has positive effects in the winter season if used in a proper way. Surface materials tend to affect solar radiation reflection and the perception of outdoor thermal comfort. This study provides a link between the theoretical background on outdoor thermal comfort and the planning or design processes. The proposed model can be used as a tool for the urban designer in order to assess the effect of design strategies on outdoor thermal comfort and creation of successful open spaces and urban environment at all. The outdoor thermal comfort can be achieved by implementing appropriate design strategies, previously simulated with assessment tools and minimizing the possible discomforts that would occur.